A common problem of the #Audi A3 is the cracking of the driver's door wires in the corrugation at the bend point. The insulation of the wiring "dries out", breaks or even short circuits occur. Fuse No. 12 in the block on the left side may burn out.
There were errors due to the unavailability of the control unit of the left door. Sometimes the door lock didn't work. There was also an error on the SRS impact sensor (9443090 Driver's side airbag crash sensor B1017 12 [136] Short to Plus).
The article of the new driver's door wiring braid 8P4971029M - costs more than 20000rub, so separate it for repair to a professional electrician friend.
To dismantle the braid of wires, you will need to remove the door trim by unscrewing 3 screws on the Torx T25.
Time codes:
0:00 Start
0:23 Removing the corrugation
0:37 How to remove the connector
1:31 Removing the door trim
3:16 Dismantling of wiring
9:28 Wiring status
=====================
My blog on DRIVE2 www.drive2.com/users/mark47/